|
The expanding universe of thermoplastic elastomers (TPEs) includes several
classes of materials whose common character is close replication of the elastic
properties of natural rubbers combined with the easy processibility of thermoplastics.
TPE families are based on styrenics, polyolefins, polyesters, polyurethanes,
thermoplastic vulcanizates (TPVs) and other materials.
Types of polyurethane (PU) elastomers commercially available include RIM-
(reaction injection-molding) processed microcellular polymers, cast and poured
elastomers made by mixing and casting reactive liquid components, sprayed polyurethane
elastomers and thermoplastic elastomers in a form suitable for conventional
thermoplastic processing. There are also several types of millable PU rubbers
that can be processed by traditional methods used in the rubber industry.
Polyurethane elastomers are noted for their toughness, flexibility (even at
low temperatures), strength, abrasion resistance, shock absorbency and chemical
resistance. Their physical properties can be tailored to a wide variety of
end uses by adjusting the mix and nature of the raw materials. Because they
are relatively expensive compared with most other elastomers, they are used
primarily in demanding applications such as automotive bumper covers/fascias/trim,
solid tires, industrial rollers, shoe soles, sport boots and various mechanical
goods.
The United States, Western Europe, China and Other Asia are currently the
major producing and consuming regions for polyurethane elastomers. In 2005,
global consumption was 1.6 million metric tons. Chinese consumption accounted
for 26% of the world total and the next highest was Western Europe with 22%.
The United States accounted for 15% of world consumption and the largest percentage
of cast elastomers. Japanese consumption is dominated by thermoplastic polyurethane
elastomers. Growth in consumption of polyurethane elastomers in the United
States will average 3.1% per year through 2010; growth in Western Europe will
average 2.2%, and growth in Japan will average 2.2%.
The following pie chart shows world consumption of PU elastomers in 2005:
The PU elastomer market is dominated largely by the major suppliers of raw
materials and prepolymers. Bayer is the recognized global PU elastomers leader
and produces or supplies all product types except millable gums in each of
the three major regions.
|
